Benefits and Limitations

It is important that women make an informed decision to screen by being aware of the benefits and limitations of
screening mammography.

Benefits

Mammograms save lives

Finding cancer early means that it is less likely to have spread and treatment can be started earlier in the course of the disease.

Approximately 1 in 8 Canadian women will develop breast cancer in her lifetime and 1 in 28 women is expected to die from the disease.

Mammograms are effective

Screening mammograms are the best method for detecting breast cancer early. Mammograms can usually find lumps two or three years before a woman or her doctor can feel them.

Research has shown a 25 per cent reduction in deaths from breast cancer among women who are screened regularly.

Your breast cancer risk increases with age

While women with a family history of breast cancer have a higher than average risk, the most significant
risk factor for breast cancer is being a woman over 50 years of age.

Over 80 per cent of new breast cancers diagnosed each year in BC are in women age 50 or older.

Limitations

Mammograms are not perfect

Not all breasts look the same on a mammogram – a woman’s age or breast density can make cancers more or less difficult to see. In general, screening mammograms are less effective in younger women because they tend to have denser breast tissue.

Mammograms do not detect all cancers

Some cancers cannot be detected on a mammogram due to the location of the cancer or the density of the breast tissue. About 25 per cent of cancers in women ages 40-49 are not detectable by a screening mammogram, compared with about 10 per cent in women older than 50.

Mammograms may lead to additional testing

On average, 9 per cent of women screened through BC Cancer Breast Screening will require additional testing to look more closely at a specific area of the breast. This does not mean that a cancer was found – over 95 per cent of the women recalled for additional testing do not have cancer.

Mammograms use low doses of radiation

The benefits of regular mammograms outweigh the risks posed by the small amount of radiation you are exposed to.